Bookmarks
Bookmarks
-
Audio Video Products and Distributors
- Acoustone Speaker Fabric
- ADTEC, Inc.
- Alcorn McBride
- All Pro
- AltaModa Unicomp
- Altinex, Inc
- AMS Neve
- Audio Upgrades
- AudioScience
- B&H Photo Video
- Barix
- BTX
- Contemporary Research
- Creative Labs
- Crouse-Kimsey
- Denon Professional
- Deva Broadcast Ltd.
- Digigram
- Easy HDTV DVR
- Eletech Message
- ELP Laser Turntable
- FMR Audio - Austin
- Fraunhofer IIS
- Gilderfluke AV Controllers
- Lynx
- Marantz Pro Audio
- MASELEC
- McIntosh Labs
- Medialon
- Niles Audio
- Orban
- Otari, Inc.
- Panasonic Industrial
- Polk Audio
- RDL Labs
- Sescom
- Shoreview Distribution
- Simon-Kaloi Message Players
- Solid State Logic
- Sonifex PC-AD2 2
- Telos Systems
- Tivoli Audio
- Wireless HDMI Extender
Audio Video Streams
- Backbone Internet Streaming
- KXT 91.7
- KXT 91.7 Listen Live
- Radio Paradise
- Shoutcast
- Smoothjazz.com
- StationRipper
- WBAP Player
- World Band Radio
Electronics
AES - IEEE
- AES E-Library
- AES E-Library Floru
- AES E-Library Proofs of an Absolute Polarity
- AES Login
- AES On-line Membership Application Form
- British Audio Engineering Society
- IEEE Xplore Login
- Institute of Acoustics - Library
- NASA STI
Application Notes
- Analog Dialogue Log Compensation
- Audio Applications Mouser Electronics
- Clairex Photocell Application Book
- CMR Resistor Matching
- Current Mirror
- Deboo Single-Supply Integrator - Maxim
- Diodes Inc App Notes Zetex
- FETching Discrete Amplifier
- Filter Designer
- High Pass Filter - Passive RC Filter Tutorial
- Jensen Transformer App Notes
- Jim Williams - EDN
- Laws For Audio Engineers
- Linear Technology Circuit
- Maxim Logic-Level Translation
- Political Correctness and Datasheets - Analog Devices
- Power Amplifier ADI AN211.pdf
- Rane Audio Reference
- THAT DN-128 PTAT
- THAT4301 Profusion
- TI - Analog Application Journal
- TI AN-30 Log Amp.pdf
- TI AN-311 Log Amp
- TI Logic Level Translation
- Understanding Common-Mode Signals
- Understanding Galvanic Corrosion
- Voltage Audio Distribution
- Voltage-Inverter IC Forms High-Efficiency Rail Splitter
- What's All This Logarithmic Stuff
- Wilson Current Source
Audio Design
- 2 Channels to Surround
- A Matter of Balance
- Audio Amp Repair Site
- Audio converter subsystem design
- Audio Designs With Opamps
- Audio Scientific - Electronic Circuits
- Audio Scientific Software
- Audio Systems Publications
- Audio VU Meter Russian Bargraph
- Base Stoppers
- Base Stoppers - Radio Board
- BBC Engineering Info
- Capacitor Characteristics
- Chin Notes on MS-Matrix Circuits
- Condenser mic dc-coupled impedance converter
- DC servo questions
- Deboo Differential DC Servo for AD851 HPA
- Differential Amp Input Impedance IEEE
- Dimitri Phono Preamp
- Distortion Jack Endino
- DIY GSSL
- Douglas Self Site
- Edcor Forum
- EDN - Line Receiver Balance
- Electronics by Uwe Beis
- Elliott Sound Products - Audio Circuits
- FM Audio Processing
- Frequency Charactersitics of AC Circuits PPT
- Gain Control Devices
- GML Model 8900 User Reference
- GSSL VCA Resistor Value Changes
- Gyraf SSL Clone
- High-Performance Balanced Interfaces
- Implement An Audio Frequency Tilt Equalizer
- Kev's Dual Mic-Pre
- Linkwitz Lab - Loudspeaker Design
- Measurements Rate SMT Low-Voltage n-JFETs
- Mic Splitters and Loading
- Microphone Site
- New Sensor Reverb Springs
- Noise in Audio Amplifiers
- Notes on Audio Op-Amps
- Op Amp Shootout Link
- Op Amp Shootout Table
- Pass D.I.Y.
- Pete Millett's DIY Audio
- Phantom Supply
- Phase distortion
- Pots - The Secret Life of Pots
- Practical Line-Driving Current Requirements
- PreSonus
- Quadraphonic Manuals
- Recording Studio Design - Google Book Search
- Renardson Audio Amplifier Design
- Russ Hamm Tubes vs. Transistors
- Selecting Mic Preamps
- Seventh Circle DIY Mic Preamps
- SG-Acoustics · Samuel Groner
- Simple Voltage Regulators Output Impedance
- Simple Voltage Regulators Part 1- Noise
- Simple Voltage Regulators Part 2-Noise
- SQ Encoding Decoders
- Stereo PPM Meter
- Studer 90 Degree Filter
- Technical books online
- The Current Output DAC
- Towards a differential active crossover
- TransLines-LowFreq
- VCA and Op Amps Form Simple VCO
- Walt Jung
- Zen I-V Converter - diyAudio
Audio Equipment Service
- Blevins Audio
- Dan Alexander Audio
- JRF Magnetics
- Objective Audio
- Speaker Repair Pros
- Squarewave Industries
- Studio Electronics Dave Kulka
Audio Software
- Acoustica Audio Software
- ARTA
- Audacity Nyquist Plugins
- Audio Plug-Ins
- Audio Restoration Brian Davies
- AudioTester
- Computer Audio
- David Taylor Utilities
- DSP Guru
- E-MU 0404 PCIE Review
- E-MU 0404 Windows 10
- FLAC vs Wav
- Frequency Response Plotter
- Jriver Phono Streaming
- K-Meter Martin Zuther
- Pure Bits Audio Analyser
- Rightmark Audio Analyser
- Roland Quad Capture Manual
- Room EQ Wizard
- SpectraPLUS
- TrueRTA
- Visual Analyser
- Will Pirkle
- YMEC
Books
- Handbook for Sound Engineers - Glen Ballou
CAD
- ABACOM Electronics Design Software
- CircuitLab Simulator
- DFM Now
- EAGLE Layout Editor
- Express PCB
- ExpressPCB Parts
- Graphicode
Calculators
- American Wire Gauge Table
- Audio Calculations
- CalcTool: RLC or LC circuit calculator
- CircuitCalculator Std Values
- E96 Resistor Calculator
- Electronics Calculators
- Logarithmic Attenuator Calculator
- Meter Scale Drawing Tonne Software
- Noise Calculator - TI
- R-C Filter Calculator
- Sallen-Key Low-pass Filter Design Tool
- Sallen-Key Low-pass Filter Design Tool - Result
- Scale-O-Matic
- SDS Labs Java Stepped Attenuator
- THAT1510 THAT1512 Gain Calculator
- Thermal Noise Calculator
- Tilt EQ Calculator
- Transformer Turns Ratio Calculator
- Wire Fusing Currents
- Wire Parameter Calculator
- XL Log and Inverse Log
Circuit and Link Collections
- Antilog Converter Linearizes Carbon Dioxide Sensor
- Circuits Bil Bowden
- A 12-V Split Rail From A 5-V Bias
- David Knight EE
- Differential Amp Has 6dB Lower Noise, Twice The Bandwidth
- Discover Circuits
- ePanorama
- Harry's Homebrew Homepage
- Headphone Amplifier
- Homo ludens sitemap
- Jim Williams, AN13, & Op Amp Wizardry
- LED Bargraph
- LM555 Creates Power Driver
Clocks
- ClockParts.com
- GPS Synchronized Nixie Clock
- IC Digital Clocks
- Nixie Clock Tube Clock Database
- Nixie Stuff
- Quartex® Atomic Clock Movement
Components
- Abracon Corporation
- Accu Bell Sound Reverb
- Alps Pot Tapers
- AQY282S Panasonic Electric Works Solid State Relays
- Aries Adapter Dip to TO
- Audio Maintenance Limited Conductive Plastic
- Audio Maintenance Single Gang Pots
- Bel HAD15-0.4-AG Bipolar 15V Supply
- Belden 9451 Technical Data Sheet
- Bourns, Inc.
- Brown Dog SMT-DIP Adapters
- Buckeye Enclosures
- Capacitor Codes - Transwiki
- CCFL backlight lamps
- Cinemag Transformers
- CIT Switch F-Series
- Coilcraft Common Mode TRS Filter
- Collective Cases
- Cooper Versa Pack Inductors
- Cornell Dubilier
- DACT home page
- Digi-Key - 294-1085 Heatsink
- Digi-Key JST VHR-5N
- DIY In HK Shop
- Duracell | Global Technical Product Data Sheets
- E96 Values Logwell
- EDCOR Electronics
- Eljintek Switching Power Supplie
- Elma Components
- EMA 1710 LCD Analog Meter
- EP Board SMT Adapters
- Futurelec ICL8038CCPD
- Goldpoint Attenuators
- Goldpoint Level Controls
- Goldpoint Prices
- Heatsinks USA
- HiFimeDIY UX1 ES9023 USB DAC+SPDIF/USB Converter
- Hudson Deep Drawn Metal Manufacturing
- Illinois Capacitor
- Jensen Transformers
- JST Connectors
- Keystone Electronics - Brackets
- KKB1031S28 Precision Electronics Corporation
- Knobs - SELCO Products
- KRL Bantry Components
- Lorlin Rotary Switches
- Mean Well
- Meter Sales
- Mic Input Common-Mode Choke
- miniDSP Kits: DIGI-FP
- Mouser Alpha Pots
- Mouser Nichicon Aluminum Electrolytics
- Mouser Nichicon Audio Caps
- Mouser Vishay Z Foil
- Mouser Vishay Z201 Resistors
- Mouser WIMA Film Capacitors
- Mouser WIMA Radial Lead Film Capacitors
- Newark - Multicomp Board Components
- Nichicon
- Nichicon Aluminum Electrolytic Selector
- NTE Fusible Resistors
- NTE Semiconductors
- Ohmite - MOX200001007JE - RES 1G OHM 1/4W 5% AXIAL
- OKW Enclosures and Knobs
- Omeg Potentiometers and Switches
- ON Semiconductor NP0080TA
- Panasonic Electric Works
- Percy Audio
- Pilot Lamps Kens Electronics
- Potentiometer ALPHASTAT
- Precision Resistor PT146
- Precision Resistor Temperature Compensators
- Pro Speaker Parts - Small Steel Boxes
- RCD PTC Resistors
- Redco Gotham GAC-2 Foil
- Redco Mogami W2929 4 Conductor 28AWG Ultra Flexible
- Reverb Springs CE Distribution
- Scientific Conversion Transformers
- SDT101-Platinum Thin Film Thermal Sensors
- Selco Products
- Sifam
- Silonex Inc. Home Page
- SPDIF 41 ReceiverMUX Module
- Sylvania 90MB Lamp IG-18
- Tamura Transformers
- TDK
- TI SMT DIP Adapters
- TKD Audio Controls
- Toshiba
- Tyco FRN25J10R Flameproof
- Tyco RGP0207CHK1G0 1G Resistor
- Visahay 1N4001GP
- Vishay
- Vishay BC Components
- Vishay Flameproof Resistors
- Vishay Resistor CMB0207
- Vishay Resistor SMM0204
- Wurth Elektronik Midcom, Inc.
Datasheets
- ADI AD4627 Bifet Op Amp
- ADI AD8510 Bifet Op Amp
- Chipdir
- Datasheet Catalog
- DataSheets Page
- Electronic Component Datasheets
- LT3571 - 75V DC-DC Converter
- MC33078
- Motorola Semiconductor Library
- TI OPA1612
- TI PCM2906
- TI PCM4202
- TI TL072
- TI TLE2426
Displays
- Counting & display tubes
- LCD VU Oscilloscope RTA, Envelope, Goniometer
- Nixie Tubes - Nixie Röhren - Nixie World
- Noritake Displays
- Vacuum & Incandescent Displays - Surplus Sales
Distributors and Vendors
- All Electronics Corp
- Allied Electronics
- Alps Electric
- Amplified Parts
- Apex Electronics
- Arcade Electronics
- Audio Accessories
- Audio Shop Parts
- B and A Electronics
- BGMicro
- Botron Static Control Products
- CEDOS
- Ceitron Sanken Semiconductor
- CIT Relay
- Das Musikding
- Digi-Key Corporation
- DIY Controls
- Don Audio
- Electronic Goldmine
- Electronic Surplus
- Electronics Websites
- Electronix Express
- Fedco Electronics Batteries
- Front Panel Express
- Futurlec
- Global Specialties
- Hammond Mfg
- Hisco
- iDefender USB Isolator
- IMS Meters
- Information Unlimited
- Jameco
- JKL Lamps
- JLM Audio Products
- John Hardy Co.
- Madisound Speaker Store
- Master Electronics
- McMaster-Carr
- Mouser Electronics
- Newark
- Newark MultiComp Brands
- Novus Plastic Polish
- Par-Metal Products
- Parts ConneXion
- Parts Express
- PartStore
- PIHER Potentiometers
- Pioneer Electronics Parts
- Precision Resistor
- PrimeLED LED Bargraphs
- Profusion plc
- Radio Spares RS Components
- Sager Electronics
- Screaming Circuits
- Sescom
- Skycraft Parts Surplus
- Small Bear Electronics
- Spark Fun Electronics
- Sphere Components
- State Electronics - Potentiometers
- StayOnline.com - Power Products
- Summit Electronics
- Surplus Resources
- Surplus Sales of Nebraska
- TMA WIMA
- Toronto Surplus
- Triode Electronics
- TTI Inc.
- TubeDepot
- Union Electronic Distributors
- Vishay
DIY
- Aether Machine
- Building your own stompbox
- How to design valve guitar amplifiers
- JLM Audio Shop
- K7000 Velleman Signal Injector Tracer Kit
- QKits
Fasteners and Hardware
- 1/4-20 ACORN CAP NUTS, ALUMINUM | Fastenal
- Albany County Fasteners
- Fastener Mart
- MiniTec T-Slotted Aluminum Extrusions
- West Coast Lockwasher
Forums
- A Simple 10W Class-A Amp Using the DRV134 - diyAudio
- Amplifiers - TI E2E Community
- Audio Amplifiers Forum - Audio Amplifiers - E2E
- Audio Asylum
- Balanced wiring from Din - Vinyl Engine
- Bob's Mailbox WK Post
- Compressor Post
- Digitizing vinyl - Page 40 - diyAudio
- Direct-Coupled Input-Capacitorless Active Mic Preamp - Prodigy Pro Archive
- DIY SQ Decoders
- DIY Synthesizer - German
- diyAudio Forums
- Electro-Music
- Electro-Music DIY Hardware and Software
- Electro-Music Dome Filter
- Electronic Equipment Repair
- FCS MSP-02 custom analog Mid/Side processor - Gearslutz.com
- Gearslutz
- Gearslutz Pro Audio Community - Mastering for Vinyl
- Group DIY
- Group DIY Post Headphone Amp
- Has anyone tried the Foote P3500?
- Home Recording
- Low-distortion Audio-range Oscillator - Page 21 - diyAudio
- Low-distortion Audio-range Oscillator - Page 686 - diyAudio
- Mastering Insert Switchers
- New Dual Class-A Headphone and Line Amp from Wayne Kirkwood - Gearslutz
- Prodigy Professional :: View Forum - Drawing Board
- Prodigy Professional :: View topic - A Direct-Coupled Input-Capacitorless Active Mic Preamp
- Products | Foote Control Systems
- PRW - Audio Recording and Music Production
- Kits Solve a Multitude of Problems - Radio World
- Real Gear Online
- Simple Class A Headphone Amp Using THAT1646 - diyAudio
- Software rumble filters - Vinyl Engine
- SOS
- Texar Audio Prisms - Radio Discussions
- The Death Of Surplus - Hackaday
- Neumann BSB 74 Acceleration Limiter - The Secret Society of Lathe Trolls
- TI INA163 Offset Voltage
- Vbe Matcher
- Virtual Ground (A Regulated Rail Splitter) - diyAudio
- Way to Approach Saturation in Mastering - Gearslutz
- Where have all the Low Noise Transistors Gone - diyAudio
- Zappa.com Forum
- Zappa.com MicMix Dynaflanger Schematics and Circuit Description
Heathkit
- Heathkit Catalog
- Heathkit Ham Radio
- Heathkit NU
- Heathkit Parts
- Heathkit Schematic Archive
- Heathkit Stereo Service and Repair
- heathkit-parts
- mods.dk Heathkit
- Nostalgic Kits Central - Information on Heathkit and others
History
- Alfred Gilbert
- AmericanRadioHistory.Com
- Analog Op Amp Design History
- Apollo Guidance Computer
- Commodor Apple
- Computer History Museum Remembering Jim Williams
- Did Commodore Contibute More Than Apple?
- EDN - Apple II goes on sale, June 5, 1977
- Gallery of rare early US Transistors
- IBM Archives - History of IBM
- IC Die Photography
- LED Museum
- Magnolia_Pipeline_Marker_Narrative.pdf
- Museum of Magnetic Sound Recording
- philbrickarchive.org
- philbrickarchive.org1
- philbrickarchive.org2
- Radio Shack Catalogs
- Radio Shack P-Box Kit
- Radio Shack P-Box Kits
- Radio World: Oliver Berliner Reveals “The Secret of the Sixteen Twelve”
- Remembering Bob Pease - TI.com
- Slide Rule Museum
- Smithsonian ICs
- Steve's Antique Technology
- Tektronix Equipment Museum
- Texas Instruments - Interactive Timeline
Instrumentation
- Philbrick Archive
- RightMark Audio Analyzer
- Sensors by Measurement Specialties
Magazines
- American Radio History
- AskWoody
- Audio Media Magazine
- AudioXpress Magazine
- EDN
- EDN - Design Ideas Archives
- EE Times Online
- EE Web
- EEM
- Electronic Design
- Electronic Design Ideas for Design
- Electronic Products Magazine
- Electronics World
- Linear Audio Magazine
- Magazines
- Mix Magazine
- Radio World Home
- SV & C
- Wireless World Articles
Mastering
- AES SAL 74/SX 74 Acceleration Limiter
- Album Dynamic Range Database
- Audacity Forum • View topic - Elliptical Equalizer (mono crossfeed filter)
- Center That Sub! - Ian Stewart Flotown Mastering
- Chicago Mastering Service
- Cutting Engineers - Gearslutz.com
- Feedback Head Plot
- Looking for 'Loudness War' Example
- Master Transfer Console
- NYT Loudness War Article
- Plangent Processes
- THE BEATLES "Rubber Soul" Stereo Mix: Why the Return to Hard-Pan L&R? - Steve Hoffmans
- Traditionally, bass is usually in mono... - Gearslutz Pro Audio Community
- Vinyl Mastering FAQs
- Why do waveforms sometimes look lop-sided ?
Mid Side
- Buzz Audio MS Compressor
- Mid Side Ceiling Speakers - AVS Forum Home Theater
- Mid Side Mic Recording Basics
- Mid Side Speaker System - Raw Sound
- Mid Side Speakers - Speakerplans Forums
- Space Station MS Amp
Patents
- Dynamic Range Expander - Rogers
- Hutson Semi Patent
- Improved Dual Channel Amplifier System - Dow
- Multiplier Circuit - Gilbert
- Ohmically Isolated Input Circuit - Meyer
- Real Time Cochlear Implant Processor - Scott and Kirkwood
- Reverberation Apparatus - Hall
People
- Bob Pease Dies
- Burwin Audio
- Jim Williams Dies
- Leo Hoarty
- Richard L. Hess
Phono Preamps
- 78 RPM and RIAA Preamplifier
- A Paul Kemble web page - sundry styli interfaces.
- Amazon Parasound - Zphono MMMC Phono Stage with USB
- AT-208DE
- Balanced Unbalanced Tonearms Technics 1200 1210 MKII
- Caruso Preamp Schematics - Lathe Trolls
- Denon DL-103R And DL-103 Reviews
- DW 999 Pre-preamplifier Manual
- Georg Neumann GmbH - History Part 4
- HPS 3.0 Phono Preamp Schematic
- JICO Stylus
- KAB Electro Acoustics
- Leach Moving Coil Head Amps
- Leo Hoarty Explains SugarCube Vinyl Ripping System
- Low Noise Design Schematics
- LP Calibration in The Mastering Room Forum
- MC Preamp Design ZTX851 Post
- Ortofon Accessories
- Pfanstiehl 759 Stylus
- Phono Cartridge Loading
- Phono Preamp
- Phono Replay Equalisation - IASAA 5.2.6
- Restoring Vinyl Records
- RIAA and the Neumann Pole
- RIAA Curve
- Stereo Sauce - FRANCINSTIEN
- Technics MN6042 Upgrade | fidelisanalog.com
- The Derumbleizer
- The Vinyl District
- V-M Audio
- Vadlyd MD12 Mk4 78 rpm & RIAA Phono Preamplifier
- Wavestream Kinetics Archival Phono Stage
- Website of Wayne Stegall - Digital Phono Equalization
Polarity
- AES Observations Audibility of Acoustic Polarity
- AES Observations Audibility of Acoustic Polarity Comments
- AES Real-World Audio Wave Form Asymmetries
Power Amps
- Amps Lab
- Class-A 10W Amp
- Class-A Amplifiers explained
- Connex Electronic
- Hiraga 20W Class-A
- JLH Class A revealings - Graham Slee
- Leach Amp Plans
- QKIts FK667
- Neurochrome Audio
Power and Grounding
- AC Power - Wikipedia
- Are smart meters accurate
- British Residential Wiring
- Homeline HOM2175SB Surgebreaker
- Mains Earthing Systems
- Power Outage US
- TED The Energy Detective
- Watt, VA, Power Factor
Radio RF
- 10-meter band
- Double Balanced Mixer - Theory Circuit and Operation
- Rfwel 3G-4G Data Antenna
- TV Signal Analysis
Schematics
- Audio Equipment Schematics
- Audio Schematics and Manuals
- dbx Equipment
- dBx Schematics
- dbx® Literature Downloads
- HiFi Engine Service Manuals
- Manuals KO4BB
- Mic Schematics
- Microphone Schematics
- Online Schematics
- Orban ftp Site
- Technician's Filing Cabinet
- Vintage German Modules
Semiconductors
- Advanced Linear Devices
- AKM Semiconductor USA
- Allegro MicroSystems Inc.
- Cemenzind - Designing Analog Chips
- Central Semi - Quad Transistors
- Cool Audio
- LEDLight.com
- Linear Systems
- LSI Computer Systems ICs
- NE-555 Website
- NTE Cross Reference
- ON Semi
- OPA211
- OPA827
- ROHM
- THAT Corporation
- THAT Upgrading Modular VCAs
- Toshiba Discrete Semiconductors
- Toshiba Application Notes
Speakers
- JBL 4311 Rebuild
- Radio Shack Minimus 7 Measurements
- Speaker Refoaming
- Tang Band Speaker
- JBL Speaker Repair Foam Kit
Synthesizer
- ARPtech
- CGS - Ken Stone's Modular Synthesizer
- Dave Rossum Interview
- DIY Stompbox
- Don's Blog_ Last of the OTA's
- Juergen Haible
- L-1 Synthesizer
- Magic Smoke Electronics
- Moog Archives
- Muff's Modules Synth Index
- Music From Outer Space
- Music From Outer Space VCO
- Seb's Synth-DIY Pages - Bench PSU
- SSM2040-Style VCF
- SSM2164 Dual VCA
- Step Sequencers - DIY Audio Electronics Kits
- Synth DIY
- Synth DIY Datasheets
- Synthesis Technology
- Synthesizers.com
Test Equipment and Tools
- Agilent
- Agilent Manuals
- Chapman 7331 Allen Head SAE Metric
- Deva Broadcast Ltd.
- Equivalent Series Resistance Meter
- Fluke 8050 LED Replacement
- Fluke Parts
- Global PB-104
- Ideal Industries 34-801 Desolder Pump Replacement Tip
- Leader LBO518 Manual
- Low THD Oscillator - Toli's DIY
- mods.dk Manuals
- P Millet Soundcard Interface
- Probe Master
- QA400 Audio Analyzer
- QT-59S - Solderless Breadboard
- Rigol Test Equipment
- Rousseau WSA1019 Workbench
- SMT Soldering You Tube Vid
- SpectraPLUS Audio Analyser
- Tek Attenuators
- Transistor Matching
- VintageTek
- Weller 400 SPONGE AND TRAY
- WW Cannon
- YMEC Audio Measurement
Vintage
- Antique Radio Classics
- Bakelite Cleaning
- Dweezil Zappa A Son of (a Mother of) Invention
- Eddie Ciletti
- How to design valve guitar amplifiers
- HP Museum
- IGS Audio - Photocell T4BX
- JH-500 Docs
- Manual Archive
- Manuals-Hickok-800a
- Museum of Magnetic Sound Recording
- Nixie Tube Page
- Nostalgic Kits Central - Information on Heathkit and others
- Panasonic SA-30
- Solid State Tube Replacements - The 1L6
- Tape recorder bias frequencies
- The Philbrick Archive
- Tube Data Sheets
- Vintage 47 Amps